Typical trucks with vacuum tanks (hereinafter referred to as “vacuum trucks”) often include a storage such as a cylindrical tank of sufficient construction to withstand a typical external pressure of 15 psi and an internal pressure from 15 psi for non-code tanks to 35 psi for U.S. Department of Transport (DOT)/Transport Canada (TC) 407/412 certified pressure vessels. The tanks are attached to a vacuum pump that may consist of a hydraulically driven air or liquid-cooled vane pump or a much larger, more powerful positive displacement blower or liquid ring vacuum pump.
In order to leverage the typically higher horsepower and torque of the truck chassis engine, a transfer case is often used to tap into the main truck chassis engine driveline in order to transfer drive to the blower. For example, in operation, drive is provided to the blower when the vacuum truck is parked and drive is no longer required to the wheel axles. Transfer cases can have complex components and moving parts in order to provide these switch modes of operation. Often, since the blower and the engine are located on the same side of the transfer case, many transfer cases have components which provide U-directional angles to transfer the drive from the engine to the blower.
In some conventional systems, the positive displacement blower is connected to the transfer case, and the blower is also mounted to be nested within the main frame rails of the truck chassis. However, this type of system can be inflexible when trying to incorporate or retrofit within existing systems, and may make activities such as, for example, installation, replacement, removal and/or repair of the blower to be cumbersome and even impractical in many applications.
It may also be cumbersome to provide proper alignment between the blower and the transfer case. Often, the components of the engine and transfer case are not perfectly horizontal with reference to the truck or to the ground. For example, discrepancies in alignment angle between the transfer case and blower could provide additional stress between the intermediary attachment components.
Additional difficulties with existing systems may be appreciated in view of the detailed description of example embodiments, below.